Microdialyzer apparatus

ABSTRACT

A device for use in performing equilibrium dialysis studies with very small volumes of solution (0.100 ml. or less, for example). The device is of sandwich construction with a permeable membrane being sandwiched between two layers of elastic, fluid-impervious material which contain fluid-receiving pockets and which are disposed under pressure between fluid-impervious rigid platelike outer wall elements.

United States Patent Inventors William 11. Riley;

Richard H. Reitz, both of Midland, Mich. 875,020

Nov. 10, 1969 Nov. 30, 1971 The Dow Chemical Company Midland. Mich.

Appl. No. Filed Patented Assignee MICRODIALYZER APPARATUS 5 Claims, 3 Drawing Figs.

US. Cl 210/321 lnt.Cl 801d 31/00 Field of Search i. 210/22,

[56] References Cited UNITED STATES PATENTS 3,211,645 10/1965 Ferrari 210/321 X 3,333.706 8/1967 lsreeli..... '210/321 3,341,299 9/1967 Catravas. 23/253 X 3.425.560 2/1969 Smythe 210/321 X Primary E.raminerF rank A. Spear, .l r. Attorneys-Griswold and Burdick and Earl D Ayers MICRODIALYZER APPARATUS BACKGROUND OF THE INVENTION This invention relates to dialysis apparatus and particularly to microdialyzer apparatus,

Although the desirability of using microdialysis techniques has been recognized that, the practice has been limited because of the difi'lculty in manipulating dialysis tubing sacs or the expense of securing sandwich-supported devices which do not leak.

Accordingly, a principal object of this invention is to provide improved microdialyzer apparatus.

Another object of this invention is to provide improved, more economical microdialyzer apparatus.

A further object of this invention is to provide improved, easy to use and easy to assemble and disassemble microdialyzer apparatus.

In accordance with this invention there is provided microdialyzer apparatus including a pair of elastic, fluid-impervious sheets usually having a plurality ofcutout parts which communicate with one edge of the sheets, the cutout parts in each sheet being aligned with each other and separated by a penneable membrane. Rigid backup sheets are held under pressure against each of the elastic sheets to define fluidtight pockets with the cutout parts.

The invention, as well as additional objects and advantages thereof, will best be understood when the following detailed description is read in connection with the accompanying drawing, in which:

FIG. 1 is a plan view of apparatus in accordance with this invention;

FIG. 2 is a side elevational view of an elastic sheet element in accordance with this invention, and

HO. 3 is a sectional view taken along the line 33 of FIG. 1.

Referring to the drawing, there is shown microdialyzer apparatus, indicated generally by the numeral 10, comprising backing plates 12, 14, usually made of glass, elastic sheet elements 16, 18, usually made of so-called medical or food-grade Silastic sheeting; and a permeable membrane 20, a cellulose membrane, for example, sandwiched between the elastic sheets 16, 18.

The assembly is held together, under pressure by clamps 22, 24.

Referring to FIGS. 2 and 3, it may be seen that the elastic sheets 16, 18 each have cutout parts 26a, 26b, respectively, which are aligned with each other when the apparatus is assembled for operative use. Each of the cutout parts 26a, 26b communicates with a lengthwise edge of its elastic sheet (28 in FIG. 2).

1n the apparatus as assembled, a plurality of fluid-receiving pockets are formed with the cutout part of the elastic sheets forming sidewalls and the membrane 20 or backing plate 12 or 14 forming the front wall and backwall, respectively.

A stopper 30, shown in FIG. 3, usually closes the pockets after they are loaded with liquid.

In operation, as is well known in the art, measured volumes of different liquid-based materials are placed in respective pockets separated by the membrane 20, and usually are vibrated to shorten the time required for sufficient dialysis to take place The amount of liquid-based material remaining in each pocket is then carefully withdrawn and measured.

While the rigid plates 12, 14 are usually made of glass, other materials which are rigid, fluid-impervious and nonreactive with the materials involved in the dialysis may be used.

Similarly, the sheets 16, 18 may be made of any suitable elastic material which is fluid-impervious impervious and nonreactive to the materials involved in the dialysis.

The simple sandwich-type construction is easily assembled and disassembled, easily cleaned, and is inexpensive to manufacture.

ln one example of apparatus in accordance with the invention the sheets l6, 18 are made of Silastic medical grade material 0.120 inch in thickness, 1 inch wide and 6 inches long. The cutout parts are made using a No. 4 (for example) cork borer centered three-eighths inch below one edge and spaced apart at least one-half inch. Small channels are cut from the cork borer bored holes to the adjacent edge of the sheet with a razor blade. The elastic sheets are then glued to 1- inch by 6-inch by A-inch plate glass by Silastic medical adhesive, Brand A, and allowed to set 24 hours before using. In some instances gluing of the sheets 16, 18 to the backing plate is not necessary.

Rubberlike silicone materials other than Silastic sheeting may be used to make the sheets 16, 18.

What is claimed is:

l. Microdialyzer apparatus comprising a sheet of permeable membrane, a pair of sheets of liquid-impermeable elastic material, said sheets each having one side abutting against said membrane, each of said sheets having at least one cutout part, each of said cutout parts communicating with an edge of its sheet, said sheets being so aligned that identical cutouts are adjacent to each other on opposite sides of said membrane, a pair of rigid liquid-impermeable backing plate elements, one of said backing plate elements abutting against each of said sheets on the side of the sheet which is remote from said membrane, said plates covering said cutout parts, clamping means, said clamping means being coupled across said backing plates, and means for capping said cutout parts along said edges.

2. Apparatus in accordance with claim 1, wherein said backer plates are made ofglass.

3. Apparatus in accordance with claim 1, wherein said sheets are made of medical or food-grade rubberlike silicone sheeting.

4. Apparatus in accordance with claim 1, wherein each of said sheets has an array of cutout pans, each of said cutout parts being the same size.

5. Apparatus in accordance with claim 1, wherein said sheets are bonded to said backing plates. 

1. Microdialyzer apparatus comprising a sheet of permeable membrane, a pair of sheets of liquid-impermeable elastic material, said sheets each having one side abutting against said membrane, each of said sheets having at least one cutout part, each of said cutout parts communicating with an edge of its sheet, said sheets being so aligned that identical cutouts are adjacent to each other on opposite sides of said membrane, a pair of rigid liquid-impermeable backing plate elements, one of said backing plate elements abutting against each of said sheets on the side of the sheet which is remote from said membrane, said plates covering said cutout parts, clamping means, said clamping means being coupled across said backing plates, and means for capping said cutout parts along said edges.
 2. Apparatus in accordance with claim 1, wherein said backer plates are made of glass.
 3. Apparatus in accordance with claim 1, wherein said sheets are made of medical or food-grade rubberlike silicone sheeting.
 4. Apparatus in accordance with claim 1, wherein each of said sheets has an array of cutout parts, each of said cutout parts being the same size.
 5. Apparatus in accordance with claim 1, wherein said sheets are bonded to said backing plates. 